Suspension device for equalizing the strain on elevator cables



Jan. 116, 1923. E

1. E. EVANS.

SUSPENSION DEVICE FOR EQUALIZING THE STRAIN 0N ELEVATOR CABLES.

2 SHEETS-SHEET 1.

FILED DEC. 30| I920.

Jan. 16, 1923.

v J.E. EVANS. fl SUSPENSION DEVICE FOR EQUALIZING THE STRAIN 0N ELEVATORCABLES.

2 SHEETS-SHEET 2.

FILED DEC. 30, 1920.

I Jrwei% W aw Patented Jan. 16, 1923.

JOSEPH'E. EVANS, OF BEDFORD, INDIANA,

ASSIGNOR OF ONE-FOURTH 'IO OLIVER M.

CLIFFORD, OF ST. LOUIS, MISSOURI.

SUSPENSION DEVICE'FOR EQUALIZING THE STRAIN ON ELEVATOR CABLES.

Application filedbecemberfifl, 1920f Seria1I Io. 433,977.

To all whom it may concern."

Be it known that I, Josnrn E. EVANS, a citizen of the United States,residing at Bedford, in the county of Lawrence and State of Indiana,have invented certain new and useful Improvements in Suspension Devicesfor 'Equalizing the Strain on Elevator. Cables, of which the followingis a specifi cation.

In elevators or lifts which are widely used for transferringpassengersgi-nd freight from one floor of a building to another, theelevator car is usually suspended from a group of cables which runover-a grooved pulley at. the top of the elevator shaft, the car beingcounterbalanced by weights also suspended from cables running over thepulley at the top of the shaft. \Vhilethe construction and arrangementof the parts of the hoisting mechanism varies among "variousmanufacturers of such appliances, it is in all cases usual to employ agroup of several cables, generally about a half dozen in number tosustain the car. These cables, because of unavoidable variations inmanufacture, are liable to stretch unequally, so that if they are allrigidly secured to the car they do not at all times sustain an equalload, with the result that the one which is the most unyielding andbears the greatest partot the load is apt to break. 7

In mV copending application No, 300,726,

filed May 29, 1919, I have described a suspension device intermediatethe group of cables and the car which acts through a hydraulicequalizing system of pistons and oil-tilled cylinders to distribute theload equally among the remaining cables; The object of my presentinvention is to. produce a serviceable and desirable equalizingsuspension deviee, in which similar ends are attained through a systemof pulleys connected together by an, equalizing cable, which shall notbesubject t'o objections inherent'in hydaulicl devices, and'which ingeneral shall be well adapted and designed to serve the purposes forwhich it was designed. .To this end. I have designed and inventedthenovel suspension device illustrated in the accompanying drawings andhereinafter explained and described, and my invention consistsin thenovel combination of co-operating elements and the new arrangement andconstruction of the parts of such device, the essential element thereofbeing more particularly pointed out in the appended claims, it beingunderstood, however, that variations and vention are possible withoutdeparting from the spirit of my invention or the scope of the claims.

In the accompanying drawings, 1 which illustrate the mechanicalconstruction and arrangement of the parts of a suspension deviceembodying my invention in a preferred form, Figure 1 is a side view ofthe device, showing fragments of the associated portions of thesuspension pulley, cables and elevator car; Figure 2 is a centralvertical section of the device, as indicated by the dotted section line2-2 of Figure 1, looking in the direction of the arrow; Fig. 3 is ahorizontal section, on the line 33 of Fig. 1; Fig. 4 is also ahorizontal section, on a plane belowthat of Fig. 3, as indicated by theline 14 of Fig. 1; Fig. 5 is a detail, showing the manner in which theends of the equalizing cables are anchored; Fig. 6 is a diagrammaticview, illustrating the relationship of the equalizing cable and thepulleys on the equalizing device and on the car; and F ig. 7 is afragmentary face view of a portion ofthe suspension' pulley and cables.

'The same reference characters indicate the same parts in all thefigures of the drawing. In the embodiment of my invention which will nowbe disclosed, the device is intended to suspend an elevator car from aset of six cables arranged to run over the usual suspension pulley B atthe top of the elevator shaft. The cables are divided in alternationinto two groups of three cables each, marked respectively A and A, theends of which arerespectively connected with the two opposite ends of aset'of three oscillatory bars 1 of the device. In the present instanceas shown.

the equalizer bars are of two-part construc tion, each bar consisting oftwo side members 2-2, spaced apart near the ends by shouldered spacingbolts 3, and orificed at the ends to receive the trunnions 4 of pivotblocks 5, which latter are vertically orificed to receive socket bolts 6connected to the cables in a common and Well-known manner, asillustrated. I p

' As shown, the equalizerbars are arranged transversely and slightlyoblique with respect to a vertical plane passing through the peripheryof the suspension pulley, the inclination of the bars being such thatthe modifications of my in-v cables A and A will all track truly intothe grooves of the pulley, see Fig. 7.

Arranged between the two members of each equalizer bar, and pivoted tothem centrally thereof, is a sheave 7 all three of these sheaves beingengaged by an equalizing cable 8 which also engages two lower sheaves 9secured to the frame work of the car, as will be later explained.

The equalizer bars are spaced and guided by U-shaped frame members 10,the side portions of which pass respectively between the two members ofthe equalizer bars, and the reduced lower ends of which extend throughthe flanged sides of a pair of channel bars 11 arranged sidewise, or onedge, and forming part of the top frame of the elevator car, and alsoextend througha plate 12 arranged beneath such channel bars, the lowerends of the bars 10 being threaded and provided with bolts for securingthem to the car frame.

In the construction shown in the drawing, I provide brake blocks orshoes 5, formed with a bearing lug pivoted at 5 in the pivot block 5 soas to have a limited rocking movement, and so arranged and constructedthat if by chance any cable A should break the end of the equalizer barto which it was connected will swing down, and the brake blocks 5 at theends of the bar will bring up against the sides of the associatedU-shaped frame member. However, if desired, the brake blocks 5 may beomitted, the unsupported' end of the equalizer bar in case of breakageof a cable then bringing up against the frame work of the car.

The plate 12 is formed with integral depending bearing blocks or lugs 13in which are journaled the two lower sheaves 9 above mentioned. As shownin Figs. 3 and 4, these sheaves (which are of slightly larger size thanthe sheaves 7) are arranged transversely and obliquely with respect tothe vertical plane passing through the periphery of the suspensionpulley, but are inclined to a slightly greater degree in a directionopposite that of the sheaves 7.

The equalizing cable 8 before mentioned is anchored-at its opposite endsto the frame work of the device, and consequently to the car, aconvenient method of securing it be ing illustrated in Fig. As thereshown, the daring strands of the cable (filled with ltabbitt metal)engage the flared lower end of an externally-threaded sleeve 14, whichsleeve extends through an orifice in the plate 12 and is engaged by nuts15 on the lower side thereof. As shown in Figs. 3 and 4, the ends of theequalizing cable lie in the vertical tangents of the grooves of theupper sheaves 7 and the cable passes in alternation around the sheaves 7and and tracks vertically from one sheave to the other. In Fig. 6, thesheaves are laid out in diagrammatic arrangement side by side,

to illustrate clearly the fact that whether,-- because of stretching, orirregularity in the grooves of the suspension pulley,-the cables" are ofequal length or not, the cables A will each sustain an equal portion ofthe weight of the car.

In case the equalizing cable 8 should break, the sheaves 7 will bring upagainst the top of the frame bars 10, which will then sustain the weightof the car. These members therefore serve as a safety device in ad'-dition to serving to space and guide the equalizer bars. It is obvious,however, that the weight of the car is normally sustained wholly by theequalizing cable, andthat the frame bars 10 may be omitted, if desired,though I regard them as a highly desirable portion of the device.

I claim:

1. A suspension device for connecting an elevator car to a set of cablescomprising a plurality of sheaves pivotally connected with said cablesand arranged side by side in parallel planes, 'a plurality of sheavesone less in number than said first-mentioned sheaves pivotally securedto the car and also arranged side by side in parallel planesintersecting said first mentioned planes, and an equalizing cableanchored at both ends to the car and engaging said first-mentionedsheaves and said second-mentioned sheaves in alternation.

2. A suspension device for connecting an elevator car to a set of cablescomprising a plurality of sheaves pivotally connected with said cablesand arranged side by side in parallel planes, a plurality of sheaves oneless in number than said first-mentioned sheaves pivotally secured tothe car and also arranged side by side in parallel planes, and anequalizing cable anchored at both ends to the car and engaging saidfirst-mentioned sheaves and said second-mentioned sheaves inalternation; said second mentioned sheaves being angularly arranged withrespect to said first-mentioned sheaves and arranged to cause saidequalizing cable to track vertically between said sheaves.

3. A suspension device for connecting an elevator car to a set of cablescomprising a plurality of sheaves pivotally connected with said cablesand arranged side by side in parallel planes, a plurality of sheaves oneless in number than said first-mentioned sheaves pivotally secured tothe car and also arranged side by side in parallel planes, and anequalizing cable anchored at both ends to the car and engaging saidfirst-mentioned sheaves and said second-mentioned sheaves i elevator carto an even plurality .of cables rimning over a suspension pulley andcomprising a set of equalizer bars respectlvely connected at theiropposite ends with said o. A suspension device for connecting anelev.ator car to an even plurality of cables running over a suspensionpulley and comprising a set of equalizer bars respectively connected attheir opposite ends with said cables, said bars each consisting of apair of spaced side members, of sheaves respectively journaled betweenthe side members of said bars, a second set of sheaves one less innumber than said firstmentioned sheaves pivotally secured to the car,and an equalizing cable anchored at both'ends to the car and engagingsaid firstmentioned sheaves and said second-mentioned sheaves inalternation.

6. A suspension device for connecting an elevator car to a set of cablescomprising a plurality of sheaves pivotally connected with said cables,a plurality of sheaves one less in number than said first-mentionedsheaves pivotally secured to the car, anequalizing cable anchored atboth ends to the car and engaging said first-mentioned sheaves and saidsecond-mentioned sheaves in alternation, inverted U-shaped memberssecured to the car and having their cross-portions arranged respectivelyabove and in the planes of the first-mentioned sheaves, and means formaintaining said sheaves in their respective planes.

7. A suspension device for connecting an elevator car to an evenplurality of cables running over a suspensionv pulley and comprising aset of equalizer bars respectively connected at their opposite ends withsaid cables, a corresponding set of sheaves respectively journaledcentrally in said bars, a second set of sheaves one less in number thansaid first-mentioned sheaves pivotally secured to the car, and invertedU-shaped members secured to the car and having their cross-portionsarranged respectively above and in the plane of said first-mentionedsheaves, said equalizer bars being spaced and guided by the sideportions of said U- shaped members. i

suspension device for connecting an a corresponding set elevator car toan even plurality of cables running over a suspension pulley andcornprising a set of equalizer bars respectively connected at theiropposite ends with said cables, said bars each consisting of a pair ofspaced side members, a corresponding setof sheaves respectivelyjournaled between the side members of said bars, a second set of sheavesone lessin number than said firstmentioned sheaves ends to the car andengaging said first-mentioned sheaves and said second-mentioned sheavesin alternation, and inverted U- shaped members secured to the .car andhav ing their cross-portions arranged respectively above and inthe.plane of said firstmentioned sheaves, the spaced side members of eachsaid equalizer ba'rs straddling the side portions of its respectiveU-shaped member. r

9. A suspension device for connecting an elevator carto an evenplurality of cables running over a suspension pulley and comprising aset of equalizer bars respectively connected at their opposite ends withsaid cables, said bars being arranged transversely and obliquelywithreference to a vertical tangential plane passing through the riphery ofthe sup-porting pulley, a set of sheaves respectively journaledcentrally upon said bars, a second set of sheaves one less in numberthan .said firstmentioned sheaves pivotally secured to the car, and anequalizing cable anchored at both ends to the car. and running over saidfirst-mentioned sheaves and said second-mentioned sheaves inalternation, said second mentioned sheaves being oppositely inclinedto-said first-men-' tioned sheaves and arranged in staggered repivotallysecured to the car, and an equalizing cable anchored at both lation,whereby said equalizing cable will track vertically between saidsheaves.

10. A suspension device for connecting an elevator car to an evenpluralit of cables running over a suspension pulley and comprising a setofo'scillatory equalizing members respectively oppositely connected withpairs of. said cables, a corresponding set of sheaves pivotallyconnected with said oscillatory meinber's, a second set of sheaves oneless in number than said first-mentioned sheaves'pivotally secured tothe car, and an equalizing cable anchored at both ends to the car andengaging said first-mentioned sheaves and said second-mentioned sheavesin alternation.

IIosEPH EVANS.

